1. Field of the Invention
Example embodiments generally relate to an image forming apparatus, and more particularly, to an image forming apparatus including a natural ventilator for exhausting hot air to the outside of the image forming apparatus.
2. Description of the Related Art
Related-art image forming apparatuses, such as copiers, facsimile machines, printers, or multifunction printers having at least one of copying, printing, scanning, and facsimile functions, typically form an image on a recording medium according to image data. Thus, for example, a charger uniformly charges a surface of an image carrier; an optical writer emits a light beam onto the charged surface of the image carrier to form an electrostatic latent image on the image carrier according to the image data; a development device supplies toner to the electrostatic latent image formed on the image carrier to render the electrostatic latent image visible as a toner image; the toner image is directly transferred from the image carrier onto a recording medium or is indirectly transferred from the image carrier onto a recording medium via an intermediate transfer member; a cleaner then collects residual toner not transferred and remaining on the surface of the image carrier after the toner image is transferred from the image carrier onto the recording medium; finally, a fixing device applies heat and pressure to the recording medium bearing the toner image to fix the toner image on the recording medium, thus forming the image on the recording medium.
Such image forming apparatuses may employ a fixing device incorporating a fixing roller heated by a heater and an opposed pressing roller pressed against the fixing roller to form a fixing nip therebetween. As a recording medium bearing a toner image is conveyed through the fixing nip, the fixing roller and the pressing roller apply heat and pressure to the recording medium, melting and fixing the toner image on the recording medium. Since heat conducted from the fixing device may melt developer contained in the development device or cause malfunction of the peripheral components of the fixing device, the image forming apparatus may incorporate a natural ventilator that exhausts hot air from the fixing device to the outside of the image forming apparatus.
For example, the natural ventilator may include a plurality of hot air outlets through which hot air from the fixing device is discharged. The hot air outlets penetrate a body plate disposed opposite a cover of the image forming apparatus produced with a plurality of outside air inlets penetrating the cover. As outside air enters the image forming apparatus through the outside air inlets, the hot air discharged through the hot air outlets is mixed with the outside air, travels upward through an air current channel extending from the outside air inlets to a vent situated at an upper edge of the cover, and is exhausted through the vent to the outside of the image forming apparatus.
The natural ventilator may require lots of hot air outlets that may degrade the appearance of the image forming apparatus. To address this problem, the cover is disposed opposite the hot air outlets to screen them from the user. However, the cover screening the hot air outlets may decrease ventilation efficiency and overheat itself.
Further, since the air current channel that conveys outside air upward to the vent is created between the cover and the body plate produced with the hot air outlets, as outside air horizontally enters the air current channel through the outside air inlets penetrating the cover, the outside air may not move vertically through the air current channel smoothly and therefore may not cool the cover heated by hot air discharged through the hot air outlets.